diff --git a/streamrip/bases.py b/streamrip/bases.py
index fd402d0..eadbd0a 100644
--- a/streamrip/bases.py
+++ b/streamrip/bases.py
@@ -202,6 +202,7 @@ class Track:
             return False
 
         if self.client.source == "qobuz":
+            assert isinstance(dl_info, dict)  # for typing
             if not self.__validate_qobuz_dl_info(dl_info):
                 click.secho("Track is not available for download", fg="red")
                 return False
@@ -211,6 +212,7 @@ class Track:
 
         # --------- Download Track ----------
         if self.client.source in ("qobuz", "tidal", "deezer"):
+            assert isinstance(dl_info, dict)
             logger.debug("Downloadable URL found: %s", dl_info.get("url"))
             try:
                 tqdm_download(
@@ -223,6 +225,7 @@ class Track:
                 return False
 
         elif self.client.source == "soundcloud":
+            assert isinstance(dl_info, dict)
             self._soundcloud_download(dl_info)
 
         else:
@@ -403,7 +406,7 @@ class Track:
             cover_url=cover_url,
         )
 
-    def tag(
+    def tag(  # noqa
         self,
         album_meta: dict = None,
         cover: Union[Picture, APIC, MP4Cover] = None,
@@ -871,7 +874,7 @@ class Tracklist(list):
         info = cls._parse_get_resp(item, client=client)
 
         # equivalent to Album(client=client, **info)
-        return cls(client=client, **info)
+        return cls(client=client, **info)  # type: ignore
 
     @staticmethod
     def get_cover_obj(cover_path: str, container: str, source: str):
diff --git a/streamrip/clients.py b/streamrip/clients.py
index 8b52730..51f80bf 100644
--- a/streamrip/clients.py
+++ b/streamrip/clients.py
@@ -1,5 +1,4 @@
 import base64
-from pprint import pprint
 import hashlib
 import json
 import logging
diff --git a/streamrip/metadata.py b/streamrip/metadata.py
index 7fb7d16..f14a941 100644
--- a/streamrip/metadata.py
+++ b/streamrip/metadata.py
@@ -1,4 +1,6 @@
 """Manages the information that will be embeded in the audio file. """
+from __future__ import annotations
+
 import logging
 import re
 from collections import OrderedDict
@@ -48,7 +50,10 @@ class TrackMetadata:
     """
 
     def __init__(
-        self, track: Optional[dict] = None, album: Optional[dict] = None, source="qobuz"
+        self,
+        track: Optional[Union[TrackMetadata, dict]] = None,
+        album: Optional[Union[TrackMetadata, dict]] = None,
+        source="qobuz",
     ):
         """Creates a TrackMetadata object optionally initialized with
         dicts returned by the Qobuz API.
diff --git a/streamrip/tracklists.py b/streamrip/tracklists.py
index 11444fd..307efbd 100644
--- a/streamrip/tracklists.py
+++ b/streamrip/tracklists.py
@@ -9,7 +9,7 @@ import logging
 import os
 import re
 from tempfile import gettempdir
-from typing import Dict, Generator, Iterable, Union, Optional
+from typing import Dict, Generator, Iterable, Optional, Union
 
 import click
 from pathvalidate import sanitize_filename
@@ -59,6 +59,7 @@ class Album(Tracklist):
         self.disctotal: int
         self.tracktotal: int
         self.albumartist: str
+
         # usually an unpacked TrackMetadata.asdict()
         self.__dict__.update(kwargs)
 
diff --git a/streamrip/utils.py b/streamrip/utils.py
index ab8bb43..d643014 100644
--- a/streamrip/utils.py
+++ b/streamrip/utils.py
@@ -5,7 +5,7 @@ import os
 import re
 import sys
 from string import Formatter
-from typing import Hashable, Optional, Union
+from typing import Dict, Hashable, Optional, Union
 
 import click
 import requests
@@ -52,6 +52,7 @@ def get_quality(quality_id: int, source: str) -> Union[str, int]:
     :type source: str
     :rtype: Union[str, int]
     """
+    q_map: Dict[int, Union[int, str]]
     if source == "qobuz":
         q_map = {
             1: 5,
@@ -89,7 +90,8 @@ def get_quality_id(bit_depth: Optional[int], sampling_rate: Optional[int]):
     :param sampling_rate:
     :type sampling_rate: Optional[int]
     """
-    if not (bit_depth or sampling_rate):  # is lossy
+    # XXX: Should `0` quality be supported?
+    if bit_depth is None or sampling_rate is None:  # is lossy
         return 1
 
     if bit_depth == 16:
@@ -266,6 +268,9 @@ def decho(message, fg=None):
     logger.debug(message)
 
 
+interpreter_artist_regex = re.compile(r"getSimilarArtist\(\s*'(\w+)'")
+
+
 def extract_interpreter_url(url: str) -> str:
     """Extract artist ID from a Qobuz interpreter url.
 
@@ -275,8 +280,14 @@ def extract_interpreter_url(url: str) -> str:
     """
     session = gen_threadsafe_session({"User-Agent": AGENT})
     r = session.get(url)
-    artist_id = re.search(r"getSimilarArtist\(\s*'(\w+)'", r.text).group(1)
-    return artist_id
+    match = interpreter_artist_regex.search(r.text)
+    if match:
+        return match.group(1)
+
+    raise Exception(
+        "Unable to extract artist id from interpreter url. Use a "
+        "url that contains an artist id."
+    )
 
 
 def get_container(quality: int, source: str) -> str: